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A sterol glycoside from leaves of Clerodendron colbrookianum

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Abstract

A new sterol glycoside clerosterol 3β-o-[β-d-glucoside] along with clerosterol, sitosterol, octacosanol and fatty acids has been isolated from the leaves of Clerodendron colebrookianum. Their structures have been characterised by spectral analysis and the C-24 (S/β) configuration in clerosterol was also confirmed.

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... Chromatographic partitioning of the n-hexane extract (9.0 g) of dry stem bark (2.9 kg) of A. cauliflora on silica gel using n-hexane/ethyl acetate mixtures of increasing polarity, led to the isolation of the new 22-hydroxyclerosterol (1) and the known clerosterol (2). The structures of the two compounds ( Figure 1) were established on the basis of detailed chemical and spectroscopic analyses and by comparison with previously reported data on clerosterols [7][8][9][10]. The known compound 2 was identified as clerosterol by combined analyses of HREIMS (m/z 412 [M + ], NMR spectroscopic data ( 1 H NMR, 13 C NMR, 1 H-1 H COSY, HSQC and HMBC) and by comparing its spectroscopic and physical data with those available in the literature on clerosterol [7,8]. ...
... The structures of the two compounds ( Figure 1) were established on the basis of detailed chemical and spectroscopic analyses and by comparison with previously reported data on clerosterols [7][8][9][10]. The known compound 2 was identified as clerosterol by combined analyses of HREIMS (m/z 412 [M + ], NMR spectroscopic data ( 1 H NMR, 13 C NMR, 1 H-1 H COSY, HSQC and HMBC) and by comparing its spectroscopic and physical data with those available in the literature on clerosterol [7,8]. The new compound 1 (mp: 166-168 °C) gave a positive reaction to the Liebermann-Buchard reagent, suggesting its sterol nature. ...
... Further elution with increasing EtOAc concentration afforded 241.4 mg (2.84%) of the new 22-hydroxyclerosterol (1) at n-hexane/EtOAc (9:1). The chemical structures(Figure 1) of isolated compounds were determined by means of spectroscopic methods ( 1 H-NMR,13 C-NMR, 1 H-1 H COSY, HSQC and HMBC) and by comparing spectroscopic and physical data with those of the literature[7][8][9][10]. ...
Article
In the search for new antiparasitic natural compounds from the medicinal plants from Cameroon, the new 22-hydroxyclerosterol, established as such on the basis of detailed chemical and spectroscopic analysis, was isolated from the hexane extract of the stem bark of Allexis cauliflora together with the known clerosterol. 22-Hydroxyclerosterol inhibited the growth of Trypanosoma brucei brucei cells with an ED 50 value of 1.56 µM. The compound was also established as an uncompetitive inhibitor of the glycolytic enzyme PGI of T. brucei (Ki'= 3 ± 1 µM), an uncompetitive inhibitor of mammalian rabbit muscles' enzyme PyK (Ki'= 26 ± 3 µM) and a mixed inhibitor of PyK of Leishmania mexicana (Ki'= 65 ± 10 µM; Ki= 24 ± 5 µM).
... Chromatographic partitioning of the n-hexane extract (9.0 g) of dry stem bark (2.9 kg) of A. cauliflora on silica gel using n-hexane/ethyl acetate mixtures of increasing polarity, led to the isolation of the new 22-hydroxyclerosterol (1) and the known clerosterol (2). The structures of the two compounds ( Figure 1) were established on the basis of detailed chemical and spectroscopic analyses and by comparison with previously reported data on clerosterols [7][8][9][10]. The known compound 2 was identified as clerosterol by combined analyses of HREIMS (m/z 412 [M + ], NMR spectroscopic data ( 1 H NMR, 13 C NMR, 1 H-1 H COSY, HSQC and HMBC) and by comparing its spectroscopic and physical data with those available in the literature on clerosterol [7,8]. ...
... The structures of the two compounds ( Figure 1) were established on the basis of detailed chemical and spectroscopic analyses and by comparison with previously reported data on clerosterols [7][8][9][10]. The known compound 2 was identified as clerosterol by combined analyses of HREIMS (m/z 412 [M + ], NMR spectroscopic data ( 1 H NMR, 13 C NMR, 1 H-1 H COSY, HSQC and HMBC) and by comparing its spectroscopic and physical data with those available in the literature on clerosterol [7,8]. The new compound 1 (mp: 166-168 °C) gave a positive reaction to the Liebermann-Buchard reagent, suggesting its sterol nature. ...
... Further elution with increasing EtOAc concentration afforded 241.4 mg (2.84%) of the new 22-hydroxyclerosterol (1) at n-hexane/EtOAc (9:1). The chemical structures(Figure 1) of isolated compounds were determined by means of spectroscopic methods ( 1 H-NMR,13 C-NMR, 1 H-1 H COSY, HSQC and HMBC) and by comparing spectroscopic and physical data with those of the literature[7][8][9][10]. ...
Article
Full-text available
In the search for new antiparasitic natural compounds from the medicinal plants from Cameroon, the new 22-hydroxyclerosterol, established as such on the basis of detailed chemical and spectroscopic analysis, was isolated from the hexane extract of the stem bark of Allexis cauliflora together with the known clerosterol. 22-Hydroxyclerosterol inhibited the growth of Trypanosoma brucei brucei cells with an ED 50 value of 1.56 µM. The compound was also established as an uncompetitive inhibitor of the glycolytic enzyme PGI of T. brucei (Ki'= 3 ± 1 µM), an uncompetitive inhibitor of mammalian rabbit muscles' enzyme PyK (Ki'= 26 ± 3 µM) and a mixed inhibitor of PyK of Leishmania mexicana (Ki'= 65 ± 10 µM; Ki= 24 ± 5 µM).
... Chromatographic partitioning of the n-hexane extract (9.0 g) of dry stem bark (2.9 kg) of A. cauliflora on silica gel using n-hexane/ethyl acetate mixtures of increasing polarity, led to the isolation of the new 22-hydroxyclerosterol (1) and the known clerosterol (2). The structures of the two compounds ( Figure 1) were established on the basis of detailed chemical and spectroscopic analyses and by comparison with previously reported data on clerosterols [7][8][9][10]. The known compound 2 was identified as clerosterol by combined analyses of HREIMS (m/z 412 [M + ], NMR spectroscopic data ( 1 H NMR, 13 C NMR, 1 H-1 H COSY, HSQC and HMBC) and by comparing its spectroscopic and physical data with those available in the literature on clerosterol [7,8]. ...
... The structures of the two compounds ( Figure 1) were established on the basis of detailed chemical and spectroscopic analyses and by comparison with previously reported data on clerosterols [7][8][9][10]. The known compound 2 was identified as clerosterol by combined analyses of HREIMS (m/z 412 [M + ], NMR spectroscopic data ( 1 H NMR, 13 C NMR, 1 H-1 H COSY, HSQC and HMBC) and by comparing its spectroscopic and physical data with those available in the literature on clerosterol [7,8]. Tab. 1. ...
... Further elution with increasing EtOAc concentration afforded 241.4 mg (2.84%) of the new 22-hydroxyclerosterol (1) at n-hexane/EtOAc (9:1). The chemical structures (Figure 1) of isolated compounds were determined by means of spectroscopic methods ( 1 H-NMR, 13 C-NMR, 1 H-1 H COSY, HSQC and HMBC) and by comparing spectroscopic and physical data with those of the literature [7][8][9][10]. ...
Article
Full-text available
In the search for new antiparasitic natural compounds from the medicinal plants from Cameroon, the new 22-hydroxyclerosterol, established as such on the basis of detailed chemical and spectroscopic analysis, was isolated from the hexane extract of the stem bark of Allexis cauliflora together with the known clerosterol. 22-Hydroxyclerosterol inhibited the growth of Trypanosoma brucei brucei cells with an ED(50) value of 1.56 μM. The compound was also established as an uncompetitive inhibitor of the glycolytic enzyme PGI of T. brucei (Ki'= 3 ± 1 μM), an uncompetitive inhibitor of mammalian rabbit muscles' enzyme PyK (Ki'= 26 ± 3 μM) and a mixed inhibitor of PyK of Leishmania mexicana (Ki'= 65 ± 10 μM; Ki= 24 ± 5 μM).
... Few important phytochemicals have been reported from the leaves of CG viz. verbascoside, martynoside, osmanthuside b6, olenoleic acid, b-sitosterol, colebroside A, maslinic acid, colebrin A-E (Yang et al., 2000a(Yang et al., , 2000b, clerosterol 3b-O-b-Dglucoside etc. (Goswami et al., 1996). All these claims make it a prospective choice for the development of novel phytopharmaceutical against said diseases. ...
Article
In this study, chemical, biological and toxicity profile of hydromethanolic extracts of different parts (leaf, stem and root) of Clerodendrum glandulosum Lindl. were investigated simultaneously for the first time. Total phenolic and flavonoid contents were estimated spectrophotometrically. Untargeted metabolomics was performed using GCÀMS and HPLC-PDA-MS to identify the individual secondary metabolites. Antioxidant potentials (DPPH, ABTS, FRAP, phosphomolybdenum, superoxide ion scavenging assay) were estimated and enzyme inhibition assays (a-glucosidase, a-amylase, pancreatic lipase, xanthine oxidase, angiotensin-converting enzyme) were performed. Cytotoxicity of the extracts in HepG2 and L6 cell lines along with acute oral toxicity was carried out. Leaf extract exhibited the highest phenolic (282.02 § 5.87 mg GAE/g) and flavo-noid (276.74 § 5.08 mg QCE/g) content. Significantly (p<0.05) high antioxidant and enzyme inhibition potential was found in leaf extract as compared to stem and root. Leaf extract (IC 50 : 104.11 § 0.36 mg/mL) exhibited comparatively better inhibition potential than standard inhibitor acarbose (IC 50 : 232.57 § 3.28 mg/ mL) against a-glucosidase enzyme. Chemical analysis confirmed the presence of verbascoside in all the three parts, whereas caffeic acid, other verbascoside derivatives, scutellarin, luteolin, and apigenin were identified in leaf. No cytotoxicity was demonstrated except by stem extract at higher concentration (1000 mg/mL). However, no in-vivo toxicity was demonstrated by extracts of any parts. These findings provides a brief overview on the chemical and biological propensities of C. glandulosum Lindl. with possibility of its use in the management of various ailments.
... The known compounds were identified as taraxerol (2) (Tang et al. 2012), myricadiol (3) (Kerr et al. 1996), friedelin (4) (Klass et al. 1992), quinovic acid 3-b-D-glucopyranoside (5) (Matos et al. 1986 (6) (Goswami et al. 1996), 22dehydroclerosterol (7) (Kitajima & Tanaka 1993), uncinatone (8) (Tian et al. 1993), 11,12,14trihydroxyabieta-8,11,13-trien-7-one (9) (Chang et al. 2005), clerodenone A (10) ), 9-hydroxytridecyl docosanoate (11) (Chai-Ming & Chun-nan 1994), tetracosanoic acid (12) (Zhuang et al. 2009), indolyl-3-carboxylic acid (13) (Feng et al. 2007) and clerodenoside A (14) (Tian & Sun 1995) by comparing their spectral data to those reported in the literature. ...
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A new triterpenoid bearing octacosanoate, named taraxer-3β-yl octacosanoate (1), together with 13 known compounds (2-14), was isolated from the ethanol extract of the stems and roots of Clerodendrum philippinum var. simplex. The structure of taraxer-3β-yl octacosanoate (1) was elucidated by extensive spectroscopic analysis. Uncinatone (8) and clerodenone A (10) exhibited inhibition of lipopolysaccharide-induced nitric oxide production in RAW 264.7 macrophages with IC50 values of 12.50 and 3.18 μM, respectively.
... The deshielding of the cyclopropane protons suggested the presence of a carbonyl group at C-3, which was further confirmed by the presence of a two protons multiplet at d 2.79 for the ketomethylene protons (Jian Xin et al., 1993). The double doublets at d 5.09 (7.5, 5.0 Hz) and 5.12 (J = 7.5, 9.0 Hz) were assigned to H-22 and H-23 double bond (Goswamy et al., 1996;Itoh et al., 1978). A triplet at d 5.16 (J = 6.0 Hz) confirmed the position of double bond in ring B at H-7 (Rao and Suseela, 1982). ...
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Two new triterpenoids were isolated from the n-hexane extract of seeds of Nigella sativa Linn. and identified as cycloart-23-methyl-7,20,22-triene-3β,30-diol (1) and cycloart-3-one-7,22-diene-24-ol (2). In addition, two aliphatic compounds and two known sugars were isolated from alcohol extract, and identified as 4-hydroxy undecyl nonanoate (3), 14,20-dimethyl heptacosanol (4), maltose (5), and sucrose (6). They were characterized on the basis of spectral analysis and by comparing literature data. Extraction and transportation study of sugars were also investigated, which evaluated biological phenomena.
... Five new steroids, colebrin A-E were also isolated [9] from the aerial parts of the species . Moreover, presence of βsitosterol and sterol compounds in the leaves of C. [10, 11] colebrookianum has already been reported (Figure 3 ). βsitosterol , a bioactive phytoconstituent that decrease the serum cholesterol and also have cardio protective potentiality which is a valid scientific basis for consuming it for better health in north [12] east region of India . ...
Article
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In view of extensive ethno-medicinal importance and utilization in various forms of ethnomedicinal applications of Clerodendrum colebrookianum in the north eastern region, the present paper is an effort to compile the existing information on folklore medicine uses by different communities of north eastern India. The paper also encompasses to analyze the potential aspects in scientific identification of principle compounds and formulation of drug-like leads based on basic and applied research activities and for development of sustainable exploitation and conservation strategies in the near future. The present work is an extensive review and analysis of published literature supplemented by actual field surveys conducted and consultation with local healers and peoples familiar with ethnobotanical and ethnomedicinal uses of Clerodendrum colebrookianum in different parts of the north eastern India. C. colebrookianum is known by more than thirty vernacular names among 20 different tribes and communities of north eastern region. The plant is used for treatment and cure of more than 16 different diseases and ailments. The use of young and tender leaves as decoction for antihypertensive purpose was the most common form of ethnomedicinal application for the species of C .colebrookianum among all ethnic tribes and communities in the region. A detailed investigation on the phytochemical, pharmacological properties of C. colebrookianum may lead to discover the potential lead compounds or molecules against life threatening diseases of human life such as hypertension, diabetes, etc.
... Leaf juice of G. lancifolia is taken in headache. Although, previous study showed presence of different class of phytochemicals in the leaves of C. colebrookianum [2][3][4][5][6][7][8] , and G. gnemon [9][10] , no phytochemical report was found in the case of Sarcochlamys pulcherrima and Garcinia lancifolia leaves. Moreover, in vitro antioxidant activities of leaves of these plants were not explored yet. ...
Article
The present study was undertaken to evaluate in vitro antioxidant activity of methanolic extract from leaves of four plants viz. Clerodendron colebrookianum Walp. (Verbinaceae), Gnetum gnemon L. (Gnetaceae), Sarcochlamys pulcherrima (Roxb.) Gaud. (Urticaceae), Garcinia lancifolia (Don) Roxb. (Cluciaceae), from Cachar district, Assam, India. DPPH (1,1-diphenyl 2-picrylhydrazyl) radical scavenging capacity, reducing power assay (RPA) and photochemiluminescence (PCL) assay were used for evaluating in vitro antioxidant activity. Total phenolic content (TPC) was estimated by Folin-Ciocalteu's method. Sarcochlamys pulcherrima showed highest antioxidant activity (DPPH EC50 9.70 ±1.51ppm), as compared to C. colebrookianum (121.05 ±1.09ppm), G. gnemon (255.99 ±0.82ppm), and G. lancifolia (344.96 ±0.76ppm). Highest activity of S. pulcherrima was also supported by RPA and PCL and highest TPC (0.33 mg gallic acid equivalent/mg of dry extract) amongst the plants, indicated that phenolic compound are mainly responsible for the activity.
... Leaf juice of G. lancifolia is taken in headache. Although, previous study showed presence of different class of phytochemicals in the leaves of C. colebrookianum [2][3][4][5][6][7][8] , and G. gnemon [9][10] , no phytochemical report was found in the case of Sarcochlamys pulcherrima and Garcinia lancifolia leaves. Moreover, in vitro antioxidant activities of leaves of these plants were not explored yet. ...
Article
Introduction: The current research has focused on the potentiality of medicinal plants for treatment of Candida albicans infections. Five plants viz. Clerodendron colebrookianum Walp. (Leaf), Gnetum gnemon L. (Leaf), Sarcochlamys pulcherrima (Roxb.) Gaud. (Leaf), Garcinia lancifolia (Don) Roxb (Leaf) and Euryale ferox Salisb. (Seed), used as traditional medicines in Cachar district, Assam, India were selected to evaluate in vitro activity against C. albicans. Methods: The plant samples were extracted with methanol. Agar well diffusion assay was used to test the activity of the plant extracts and broth microdilution method was used to determine the MIC. Results: All extracts showed anticandidial activity with zones of inhibition ranging from 17 to 25 mm at 2×105 µg/ml extract. E. ferox and S. pulcherrima showed the highest activity with the MIC value of 1.25 × 104 µgg/ml. The remaining extracts were comparatively less effective showing MIC value of 2.5 × 104 µg/ml. Conclusions: Anticandidial activity of the plants extracts, observed in this study highlighted further in vivo investigation and identification of the active compounds for therapeutic uses. The anticandidial activity of S. pulcherrima and G. lancifolia is probably the first report to the best of our knowledge.
... mentioned above that some potent anthelminthic principles are widely present in Clerodendrum species which ascribe them significant anthelminthic properties. The aerial parts of C. colebrookianum are reported to contain steroids, alkaloids, glycosides, β-sitosterol and daucosterol as the main chemical constituents (Goswami et al. 1996;Yang et al. 2000). It is likely that one or more of these constituents may be responsible for the reported efficacy of this plant, as there are several published reports which attest the anthelmintic actions of medicinal plants to the reported constituents of C. colebrookianum (Athanasiadou and Kyriazakis 2004). ...
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Although there are several effective drugs available for the treatment of intestinal helminths, the fact remains that they continue to remain out of reach to a vast majority of people in the world, especially in developing countries. On the other hand, there are a great many herbal remedies that are effective against common intestinal worms and are easily available to common people in developing countries. Clerodendrum colebrookianum Walp. (Lamiaceae) is a perennial shrub which is native to South and Southeast Asia. Traditionally, the leaves of this plant are used by the indigenous people of Northeast India as a remedy for the treatment of intestinal tapeworm infections. The aim of this study was to evaluate and authenticate the anthelmintic efficacy of C. colebrookianum leaf extract in experimentally induced Hymenolepis diminuta (a zoonotic tapeworm) infections in Wistar rats. The efficacy of the plant extract was assessed by monitoring the eggs per gram of faeces (EPG) counts and worm recovery rates of experimental animals, following treatment with the leaf extract of this plant at three different doses, i.e. 200, 400 and 800 mg/kg body weight, each given singly for 5 days. The results obtained revealed that the leaf extract of C. colebrookianum possesses a dose-dependent efficacy against the larval, immature and adult stages of H. diminuta. However, the efficacy of the extract was found to be considerably high only against the adult stages of the parasite. For this stage, a single 800-mg/kg dose of extract, given for 5 days, resulted into 68.42 % reduction in the EPG counts and 62.50 % reduction in the worm counts in the extract-treated group of animals, as compared to the control. The reference drug, praziquantel (5 mg/kg, single dose), however, showed slightly better efficacy and caused 95.16 and 87.00 % reductions in the EPG and worm counts of treated animals, respectively. Unlike the adult stages, the efficacy of the plant extract was recorded to be comparatively low against the larval and immature stages of the parasite, as the treatment of animals with the highest dose of extract (800 mg/kg) could cause only 37.50 and 54.00 % reductions in worm counts, respectively. The experimental evidence obtained in this study suggests that leaves of C. colebrookianum possess significant anthelminthic properties and supports their use against intestinal tapeworm infections in traditional medicine.
... C. colebrookianum is commonly found in India and south Asian countries, and considered as one of the most important vulnerable medicinal plant widely used in the treatment of hypertension and showed its potential as antidiabetic, antihypertensive, antimicrobial, cardioprotective potential and sedative properties (Chae et al., 2004). In this regard, there are reports validating the potential of plant for the discovery of sterol glycoside (Goswami et al., 1996), Colebroside A (Yang et al., 2000a) and steroids (Yang et al., 2000b); however, there is no published report about the identity and physiological capabilities of endophytic or rhizospheric bacterial population. Our study is the first report about the isolation and functional characterization of endophytic bacterial population associated with C. colebrookianum, as well as their in vitro and in vivo PGP potential. ...
Article
In this study, culturable endophytic bacterial isolates obtained from an ethnomedicinal plant Cleroden-drum colebrookianum Walp., were assessed for their diversity, in vitro screening for their plant growth promoting (PGP) activities and to use them as inoculant for in vivo PGP activities with biocontrol potential. Totally, 73 isolates were recovered from different tissues of C. colebrookianum were identified by 16S rRNA gene sequencing and phylogenetically analyzed by using BOX-PCR fingerprinting. Out of 73 isolates, 52 exhibited varying extents of antagonistic potential were selected for screening for various PGP traits. Concerning the PGP activities, the percentage of isolates positive for P-solubilisation, indolic compounds production, siderophore and ammonia production were 84.6, 92.3, 78.8 and 98.0 respectively. All isolates were positive for the production of hydrocyanic acid (HCN) and 86.5%, 84.6% and 90.3% of isolates showed significant cellulase, amylase and protease production respectively. Further, the top 10 bacterial isolates based on a bonitur scale with multiple PGP activities were screened for root surface colonization and biofilm formation ability. Out of selected 10 isolates, 9 showed significant potential for root surface colonization on tomato roots. Isolate BPSAC6 identified as Bacillus sp. was most efficient in biofilm formation as assessed with respect to the intensity of crystal violet, which further showed their potential to withstand various biotic and abiotic stresses. Furthermore, Bacillus sp. strain BPSAC6 showed a significant increase in shoot and root height as well as fresh weight after 45 and 60 d of inoculation with tomato seedlings. Additionally, biosynthetic potential of antagonistic isolate was detection by using PKSI, PKSII and NRPS biosynthetic genes. Two isolates Pseudomonas psychrotolerans and Labrys wisconsinensis were reported first time as an endophyte. At last, first time an endophytic bacterial strain Bacillus sp. BPSAC6 was reported to produce altogether three phytohormones (IAA, Kinetin and 6-Benzyladenine). This study is the first report that bacteria isolated from C. colebrookianum has biocontrol as well as PGP abilities endowed with phytohormones production and can be used for the preparation of bioinoculant for plant growth promotion.
... Acid hydrolysis of 2 yielded glucose as the sugar residue, identified by TLC and PC co-chromatography with authentic samples and the large coupling constant of the anomeric proton indicated that the glucose unit was present in the β-configuration. This was supported by the 13 18 with a sugar linked to the aglycone at C-3, as was ascertained by gHMBC correlation between C-1' of glucose (δ 100.8 ppm) and H-3 (δ 3.46 ppm). On the basis of spectroscopic data as well as comparison with literature, compound 2 was concluded to be 24-ethylcholesta-5,25-diene-3-O-β-glucoside. ...
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Chemical investigation of CH2Cl2 and MeOH extracts of Conyza floribunda have led to the isolation of (24S)-ethylcholesta-5,22E, 25-trien-3-0-glucosy(l"→ 4')-rhamnoside (1), (24S)-ethylcholesta-5,25- dien-3-0-/3-glucoside (2), cyasterone (3), stigmasta 5,22-dien-3-acetate (4), stigmasta 5,22-dien-3-ol (5), spinasta 7,22-dien-3-ol (6), 3-oxofriedooleanane (7), 3-hydroxyfriedooleanane (8), 3-acetoxyfriedooleanane (9), betullinic acid (10), quercetin 3-0-/3-glucoside (11), quercetin (12), myricetin (13) and kaempferol (14). Their structures were determined using spectroscopic and physical methods as well as comparison with data available in the literature.
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From the aerial parts of Clerodendrum inerme, two new sterols (4alpha-methyl-24beta-ethyl-5alpha-cholesta-14, 25-dien-3beta-ol and 24beta-ethylcholesta-5, 9(11), 22E-trien-3beta-ol) and a new aliphatic ketone (11-pentacosanone) were isolated together with another known aliphatic ketone (6-nonacosanone) and a diterpene (clerodermic acid). The structure elucidations were based on analyses of physical and spectroscopic data.
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Natural products represent a rich source of new chemical entities for the development of drugs for neglected diseases. Leishmaniasis still afflicts the poorest populations in the world, with 12 million cases worldwide. This work analysed crude extracts and fractions from the fruits of Cassia fistula against the most dramatic and fatal disease form of leishmaniasis, the visceral form (VL). Hexane extract from the fruits showed significant antileishmanial activity against the promastigote form of Leishmania L. chagasi. The bioguided fractionation resulted in the isolation of a sterol, clerosterol, which was further analysed in different models. Promastigotes presented an inhibitory concentration 50% (IC50) of 10.03 microg/mL and intracellular amastigotes demonstrated high susceptibility, with an IC50 of 18.10 microg/mL. Mammalian cytotoxicity was evaluated and it was demonstrated that clerosterol was 3.6-fold less toxic than the standard drug pentamidine. No antifungal activity of the isolated clerosterol was found. Future studies of the extracted compounds of Cassia fistula could be a useful tool for the development of new therapeutic agents for VL.
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Colebroside A (1), a new diglucoside of fatty acid ester of glycerin, was isolated from the aerial parts of Clerodendrum colebrookianum Walp., along with nine known compounds (2-10). Their structures were elucidated by spectroscopic and chemical methods. Compounds 2, 3, 4, 5, 7, 8, 9 and 10 have been obtained from this plant for the first time.
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Clerodendron colebrookianum Walp (family, Verbenaceae) has been used as a home remedy by the Mizo people of north eastern (NE) region of India in their folklore medicine as a cardioprotective (mainly against high blood pressure) agent. The scientific basis for their use has yet to be established. Therefore, in this investigation an attempt has been made to study the effect of different extracts of the leaves of Clerodendron colebrookianum Walp (CC) on serum lipid profile which is closely associated with many cardiovascular diseases. It was found that after administration of both crude and organic extracts the serum lipid profile, i.e. total cholesterol (TC), triglycerides (TG) and low density lipoprotein (LDL) lowered significantly (P<0.001) from their respective control except TG in methanol extract (ME)-treated rats. The decreased percentage of TC, TG and LDL after administration of crude extract (CE) and ethylacetate extract (EE) with normal diet were found to be 35, 39 and 48%, and 33, 18 and 91%, respectively, after 7 days of treatment. In case of ME the lowering of TC and LDL were noted to be 41 and 85%, respectively. Both TC and TG were lowered significantly (P<0.001) even after the administration of crude extract against high-fat diet. Significant increase of cardioprotective lipid, i.e high density lipoprotein (HDL) after administration of EE (46%) and ME (38%) was another interesting finding of this experiment. Total cholesterol:HDL and LDL:HDL ratios were significantly lower in the experimental group. Therefore, it was concluded that the leaves of CC have definite cardioprotective potentiality, and there is a valid scientific basis for consuming it for better health in NE region of India.
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The in-vitro antioxidant activities of different concentrations of the water, alcoholic, petroleum ether and ethyl acetate extracts of the dried leaves of Clerodendron colebrookianum Walp, and in-vivo antioxidant activity of the water extract was studied in experimental rat models. The results obtained from in-vitro lipid peroxidation induced by FeSO4-ascorbate in rat liver homogenate showed a significant inhibition of lipid peroxidation by different extracts of C. colebrookianum leaf. Water extracts at concentrations (w/v) of 1:30, 1:50, 1:200 and 1:1000 showed the strongest inhibitory activity over the other organic extracts, suggesting maximum antioxidant effect. Chronic feeding of the water extract to Wistar albino rats (both sexes, 150-200 g) in 1 or 2 g kg-1/day doses for 14 days significantly increased the ferric reducing ability of plasma by 19% and 40% on the seventh day, and by 45% and 57% on the fourteenth day of treatment, respectively. Thiobarbituric acid reactive substances (TBARS), as a marker of lipid peroxidation, and some cellular antioxidants (superoxide dismutase, catalase and reduced glutathione) were estimated in heart, liver and kidney. There was a significant reduction in hepatic and renal TBARS with both the doses, without any change in myocardial TBARS. There was no change in the level of antioxidants in heart, liver and kidney, except for the hepatic superoxide dismutase. The findings of this study showed that the leaf extract of C. colebrookianum increased the antioxidant capacity of blood and had an inhibitory effect on the basal level of lipid peroxidation of liver and kidney. This lends scientific support to the therapeutic use of the plant leaves, as claimed by the tribal medicine of North-East India.
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Five new steroids, colebrin A-E (1-5) were isolated from the aerial parts of Clerodendrum colebrookianum. The structures of the new compounds were elucidated on the basis of spectral evidence.
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Three new sesquiterpenes, 1 beta,7 alpha(H)-cadinane-4 alpha,6 alpha,10 alpha-triol (1), 1 alpha,5 beta-guaiane-10 alpha-O-ethyl-4 beta,6 beta-diol (2), and 6 beta,7 beta(H)-cadinane-1 alpha,4 alpha, 10 alpha-triol ( 3), together with 25 known ones, were isolated from the rhizome of Acorus calamus L. Their chemical structures were established on the basis of interpretation of spectroscopic data and comparison with those of the related known compounds.
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Reactive oxygen species (ROS) have pathogenic effects on ischemic-reperfusion injury of heart. Hence, it is important to identify natural antioxidative agents to mitigate such effects. Recently, it has been reported that Clerodendron colebrookianum (CC) leaf extract has antioxidant and hypolipidemic effects in experimental animals. The aim of this study was to examine whether acute treatment with CC extract offers protection against ischemic-reperfusion injury (IRI) and IRI-induced changes in endogenous antioxidant enzyme activities of rat heart. Isolated rat hearts were perfused using the Langendorff's technique, and 20 min of global ischemia was followed by 40 min of reperfusion. Lipid peroxidation after the ischemic-reperfusion episode was significantly reduced in the CC extract-treated heart compared to the control group and suppressed the leakage of lactate dehydrogenase (LDH) during reperfusion. Moreover, CC extract diminished the depletion of myocardial antioxidant enzymes (SOD, Catalase, GSH and GPx) after ischemia-reperfusion. Furthermore, IRI-induced cellular damage was significantly less in CC extract treated myocytes. These results indicate that CC leaf extract protects against oxidative stress and cellular injury associated with ischemic-reperfusion injury of rat heart and suggests that the protective effects of CC extract depend on its antioxidant properties.
Clerodendron colebrookianum Walp., (Fam: Verbenaceae) locally known is "NEFAFU" is widely used for curing various diseases. Here some pharmacological properties of this plant were studied using rat & mice of either sex. Methanol extract (MLE) of various concentrations (50, 100, 200 mg/kg of body wt) were tested on animals. Carrageenin induced rat paw oedema model with three hours for oedema formation was used to test anti-inflammatory activity. It was observed that the plant extract significantly inhibits the Carrageenin induced rat paw oedema. The acetic acid induced writhing test by injecting 0.6% acetic acid (i.p.) followed by injecting MLE & tail immersion test, both in hot & cold water was used to test the analgesic effect of the plant. In all the four experiments MLE (200 mg/kg, of body wt.) has been found mostly effective in inhibiting Carrageenin induced rat paw oedema, the number of writhings induced by acetic acid & elevated pain threshold in hot & cold-water test. It reduced the number of abdominal writhing induced by acetic acid and elevated pain threshold in hot tail flick test. The effect of methanol extract (MLE) on phenobarbitone induced sleeping time was also tested, here again MLE (200 mg/kg of body wt) showed remarkable prolongation in sleeping time. Seasonal variation on the activities of the plant extract was also investigated in the study. The plant samples were collected in the months of January and July of the year. It has been observed that the January collection of the plant showed higher activities in most of the parameters in these experiments and also showed significantly higher values in the proximate analysis. The leaves of the C. colebrookianum were practically found to be non-toxic.
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Two new compounds, 5-O-ethylcleroindicin D (1) and bungein A (2), together with 12 known compounds (3-14), were isolated from the aerial parts of the medicinal plant Clerodendrum bungei. The structures of 1 and 2 were elucidated as a perhydrobenzofuran derivative and a peroxide dimer by spectral and chemical evidence. Compounds 3-14 have been obtained from this species for the first time.
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Kalanchoe fedtschenkoi Raym.-Hamet & E.P.Perrier is a bush with several branches belonging to the family Crassulaceae and it is cultivated as an ornamental plant in Egypt, and mostly native in Madagascar, the name Kalanchoe is thought to be an Indian word meaning "rusty" because leaves often develop rust- colored spots with age and fedtschenkoi after Boris Fedtschenko (1872-1933), Russian traveler. The plant has no reports for phytochemical and/or biological studies till now. The present study deals with phytochemical investigation of the different constituents of aerial parts "leaves, flowers and stems" of title plant, in addition to the biological evaluation with the aim of clarifying the taxonomic position of this species. UI- Phytochemical study for isolation and identification of the main constituents of the plant: UPreliminary phytochemical screening: The fresh aerial parts "leaves, flowers and stems" of Kalanchoe fedtschenkoi revealed that, carbohydrates and/or glycosides, sterols and/or triterpenes, pyrogalloltannins, flavonoids and saponins are present in all organs under investigation. The study showed also the absence of crystalline sublimates, volatile oil, cardienolides cardiac glycosides, alkaloids and/or nitrogenous bases and anthraquinone derivatives in all the investigated organs of Kalanchoe fedtschenkoi. U Isolation and Identification: The fresh plant material (13 kg) was subjected to extraction with 70 % boiling ethyl alcohol (4 x 20 L). The ethanolic extract was concentrated by evaporation under vacuum at 40 ºC to yield (185 g) and the concentrated extract was suspended in distilled water (500 ml), then fractionated with methylene chloride to yield (15 g) , ethyl acetate to yield (5 g) , n-butanol to yield ( 25 g ) and remaining aqueous extract (140 g). Further purification and separation of each fraction are conveniently achieved by chromatographic methods. Each fraction was subjected to series of silica gel column chromatography and gel filtration (sephadex LH-20) to afford different compounds. Chromatographic purification of the CHR2RClR2R and EtOAc soluble fractions of Kalanchoe fedtschenkoi extracts furnished two known pentacyclic triterpenes (1-2), a known sterol (3), a new sterol glycoside (4), a new megastigman (5), a known flavonid (6), and a simple phenolic acid (7). The structures of the isolated compounds were established by chemical and on the basis and spectral data interpretation including; (UV, IR, EI-MS,ESI-MS, FAB-MS, P1PH-and P13PC-NMR). Carbon multiplicities of compounds isolated were confirmed by DEPT-NMR, and connectivities P1PH-P13PC were determined by P1PH-P1PH-COSY, P1PH-P13PC-HSQC and P1PH-P13PC-HMBC (2D-NMR correlated spectroscopy). Spectra (UV, IR, P1PH and P13PC NMR, P1PH-P1PH-DQF-COSY, HMQC and HMBC and mass spectrometry) for isolated compounds (1-7) were established by comparing their spectral data to those given in the literature, and identified as: Fridelin (1), Glutinol (2), (24S)-5α-Stigmasta-7,25-dien-3β-Ol (3), 24β-Ethylcholesta-5, 9 (11), 22E-trien-3-O-β -D-(2`-acetyl)xylopyranoside (4), (3S,6R,7E,9R)- megastigma-7-ene 3, 6, 9- triol (5), Sagittatin A (6), Gallic acid (7) UII- Biological Evaluation of Kalanchoe fedtschenkoi: The biological activities of the extract obtained from the leaves of Kalanchoe fedtschenkoi were performed and tested as follows: A) UEffect of Kalanchoe fedtschenkoi extract on Isolated rabbit's Heart According to Langendorff's procedure: According to Langendorff's procedure , four Kalanchoe fedtschenkoi extract was used in the following order 5mg, 10mg, 0.625mg and 1.25mg and effects on the hearts were decreasing force of contraction at all concentrations (-ve chronotropic effect ) and hearts death due to heart block (atrioventrecular block) . This indicate that this plant is cardiotoxic and canot be used at this Concentrations for heart treatment. B) UAntioxidant Evaluations: UA. Assay for DPPH free radical scavenging activity: Among the three different extracts, the EtOAc and n-BuOH extracts expected to have the highest activity in DPPH quenching (EtOAc, 60.5 %), (n-BuOH, 57.2.5%) while the CHR2RClR2R extract (27.2%) showed less DPPH activity than D,L, α-tocopherol (64.8%) and BHT (50.6%)The radical scavenging effects of Kalanchoe fedtschenkoi might be due to the hydroxyl groups. UB. Ferrous sulphate-HUR2ROR2RU-stimulated lipid peroxidation in rat tissue homogenate: Rat tissue homogenate (brain, heart and liver) is useful for investigation of lipid peroxidation, and has also been used as a preparation to elucidate antioxidant activity. Ferrous ion stimulates lipid peroxidation through various mechanisms such as the decomposition of lipid peroxides, the generation of hydroxyl radical or by forming perferryl or ferryl species. For this work, the effect of of Kalanchoe fedtschenkoi extracts for rat tissue homogenate (brain, heart and liver), the unstimulated control experiments the amount of thiobarbituric reactive substance 179 (TBARS) [MDA levels without FeSOR4R-HR2ROR2R] formed in rat tissue homogenate (brain, heart and liver) were (0.43 + 0.05 nmol malon-dialdehyde, MDA/mg protein), (0.25 + 0.02 nmol malon-dialdehyde, MDA/mg protein) and (0.18 + 0.01 nmol malon-dialdehyde, MDA/mg protein), respectively. After induction with 200 m FeP2+P-HR2ROR2R, The amount of TBARS increased to (0.88 + 0.08 nmol malon-dialdehyde, MDA/mg protein), 0.72 + 0.06 nmol malon-dialdehyde, MDA/mg protein) and (0.55 + 0.05 nmol malon-dialdehyde, MDA/mg protein) of brain, heart and liver, respectively. However, as shown in the results, adding 100-300 μg/mL Kalanchoe fedtschenkoi (CHR2RClR2R, EtOAc and n-BuOH), extracts to rat tissue homogenates (brain, heart and liver), significantly reduce MDA formation in the presence of FeP2+P-HR2ROR2R in tissue homogenates, indicating anti-lipid peroxidation activities of Kalanchoe fedtschenkoi extract. The inhibition percentages were in the range of (33.15 – 46.25%), (45.28 – 68.25%) and (27.10 – 52.75%) in brain, heart and liver rat tissue homogenates, respectively. The data obtained from the present study indicates that extracts of Kalanchoe fedtschenkoi has an anti- lipid peroxidative character with similar reaction mechanisms to those of D, L–α–tochopherol and BHT. These extracts may suppress lipid peroxidation through different chemical mechanisms, including free radical quenching, electron transfer, radical addition, or radical recombination. Further composition analysis is necessary to better understand the relationships between chemical structures/ composition and antioxidant properties. UC. Xanthine oxidase-induced generation of superoxide radical: In the present study we have investigated the inhibitory effects of Kalanchoe fedtschenkoi extracts (CHR2RClR2R, EtOAc and n-BuOH) on the activity of xanthine oxidase to fined effective inhibitory for xanthine oxidase using D,L, α-tocopherol, BHT and Allopurinol as reference compounds. The inhibitory activity of each extract is expressed in terms of ICR50R, the concentration of the extracts or isolated compounds required for 50% inhibition of the uric acid formation. The initial rate of uric acid formation caused by xanthine oxidase (0.05 U/mL; 50 μL) was (60.0 + 1.5 nmol/min). The superoxide scavenging activities of Kalanchoe fedtschenkoi extracts at concentration 100-200 μg/mL inhibit the activity of xanthine oxidase. Among the three different extracts, the n-BuOH extract has the lowest activity (55 μM), while the CHR2RClR2 Rextracts (38 μM) have the highest activities in xanthine oxidase inhibition. The results also showed the different extracts of Kalanchoe fedtschenkoi showed the highest xanthine oxidase activity than BHT (112 μM), and D,L, α-tocopherol (77μM) but less effective than Allopurinol (18 μM), These finding emphasize that Kalanchoe fedtschenkoi extracts could be better antioxidant in the superoxide scavenging process. UD. Superoxide anion scavenging activity: The % inhibition of superoxide radical generation by 100 μg/ml of (CHR2RClR2R, EtOAc and n-BuOH) extracts of Kalanchoe fedtschenkoi, and comparison with same concentrations of D,L, α-tocopherol, and BHT. The n-BuOH extract of Kalanchoe fedtschenkoi, had strong superoxide radical scavenging activity (70.1%), and exhibited higher superoxide radical scavenging activity than that of same doses of D,L, α-tocopherol (68.5%) and BHT (44.2%). The results were found statistically significant (P<0.05). The EtOAc extract (57.2%), showed slightly less superoxide radical scavenging activity than D,L,-tocopherol (68.5%) but greater than that of same doses of BHT (44.2%). The percentage inhibition of superoxide generation by 100 μg/ml concentration of CHR2RClR2R extract was found as (18.5%) and less than that of same doses of a-tocopherol and BHT (68.5 and 44.3%), respectively.
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Three mixtures of steroids (1a+1b, 2a+2b and 3a+3b) and two flavonoid glycosides (4 and 5) were isolated from the ethanol extract of branches of Porcelia macrocarpa (Warm.) R. E. Fries (Annonaceae). The steroids Stigmasta-4,25-dien-3-one (2a) and (22E)-Stigmasta-4,22,25-trien-3-one (2b) are news. The structures were elucidated by NMR and MS data and comparison with literature data of model compounds.
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Plants, animals, and other microorganisms are provided, in their genetic makeup, with a certain range of antimicrobial compounds. With respect to viruses, a few plants show resistance to their infection. This resistance, in many cases, has been associated with the protective chemicals within the plant cells which are known for their antifungal or antimicrobial property and reported to be proteinaceous in nature. Many higher plants have developed a variety of defense systems to combat pathogen attack which is essential for their survival. Some of these plants possess endogenous proteins that act as virus inhibitors. They are generally basic proteins with molecular weight ranging from 24 to 32 kDa and effective against a wide range of plant viruses. The viral inhibitors are well studied in Phytolacca americana, Dianthus caryophyllus, Boerhaavia diffusa, Cuscuta reflexa, Mirabilis jalapa, Bougainvillea spectabilis, and Celosia cristata. These viral inhibitors are most effective when mixed with the virus inoculum or when they are applied one day before or shortly after mechanical inoculation.
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Arunachal Pradesh (AP), one of the northeastern Himalayan states of India, is rich in biodiversity. The threat of destruction of certain species makes it a hotspot which merits urgent attention. A literature survey revealed that more than 21 indigenous communities and 110 sub-communities are dependent on the biodiversity for basic needs like, food, medicine, shelter, energy, veterinary care and ecosystem services. It further showed that more than 950 plant species are known to these communities as heritage Non Timber Forest Product (NTFP) due to knowledge passed over generations. Out of these, there are 215 fruits, 300 vegetables, 565 medicines, 38 minor shelter materials, 21 fuel provider and 170 other products for miscellaneous uses. Several of these species have commercial potential and could be used for increasing income and employment opportunities, especially for the poor and otherwise disadvantaged people of the region. Such species require innovative attention to enhance the value of products, which in turn would improve the standard of living of the people. However, the scaling up of commercialization might problematize sustainable management of bioresources. Therefore, this could be balanced by home gardening or domesticating the commercial species, along with scientifically improved harvesting or silvicultural operations, and establishing conservation reserves in forests. A key feature of successful approach to NTFP management will be sound monitoring and evaluation of the programme taken up for marketing and conservation of vulnerable species.
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The structures of two classes of glycolipids, acylglucosylsterol and glucosylsterol, from snake epidermis have been determined by chemical, spectroscopic, and gas-liquid chromatographic methods. The acylglucosylsterol consists of a glucose molecule attached to cholesterol and an ester-linked fatty acid on carbon 6 of the sugar. The major ester-linked fatty acids are palmitic, stearic, and oleic. The glucosylsterol consists of glucose attached to cholesterol. These unusual glycolipids may play a role in epidermal barrier function in snakes and it is concluded that these sterol glycosides may remain in the reptiles as a vestige of a more primitive barrier-forming mechanism.
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A mixture of acylglucosylsterols was isolated from the green fruits of Momordica charantia (balsam pear or bitter gourd) and the structure elucidated by high field 1H NMR, 13C NMR, FTIR and mass spectrometry and chemical modification studies followed by spectral and chromatographic analysis. The major acylglucosyl sterol was 3-O-[6′-O-palmitoyl-β-d-glucosyl]-stigmasta-5,25(27)-diene while the minor component was 3-O-[6′-O-stearyl-β-d-glucosyl]-stigmasta-5,25(27)-diene. The isolation and structure elucidation of these acylglucosyl sterols are reported for the first time.
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A substantial amount (ca 18%) of the sterol found in the seeds of Cucurbita maxima had a Δ-bond and consisted of seven components. They were identified as 25(27)-dehydroporiferasterol, clerosterol, isofucosterol, stigmasterol, sitosterol, campesterol and codisterol. The C-24 configuration of each of the sterols was unequivocally established by a 1H NMR spectral comparison with authentic standards. This is the first time codisterol has been found in a higher plant and also the first time the structures and configurations of the Δ5-sterols from a Cucurbitaceae species have been clearly characterized.
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Extracts of the roots of Clerodendron colebrookianum Walp. contained triacontane, clerodin, (24s) ethylcholesta–5,22,25–triene–3β–ol, α–amyrin, β–sitosterol and clerodolone. (24s) Ethylcholesta–5,22,25–triene–3β–ol, β–amyrinand β–sitosterol were obtained from the roots of Clerodendron paniculatum L. while the roots of Clerodendron phlomoides Willd. gave ceryl alcohol, clerodin, clerosterol and clerodendrin–A.
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Eighteen sterols were isolated from the aerial parts ofKalanchoe pinnata (Crassulaceae) including four novel sterols,viz. (24R)-stigmasta-5,25-dien-3β-ol (24-epiclerosterol), (24R)-5α-stigmasta-7,25-dien-3β-ol, 5α-stigmast-24-en-3β-ol, and 25-methyl-5α-ergost-24(28)-en-3β-ol. 24-Epiclerosterol and its Δ7-analog occur together with their 24S/β-epimers in the same plant making this the first report of the isolation of both C-24 epimers of Δ25-unsaturated 24-alkylsterols from a non-marine organism. Iodine-catalyzed isomerization of stigmasta-5,24-dien-3β-ol (24-ethyldesmosterol), the main sterol ofK. pinnata, yielded 24-epiclerosterol among other products.
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